Multicylinder oscillating pump or compressor



Oct. 23, 1934. F, SMITH 1,977,740

MULTICYLINDER OSCILLATING PUMP OR COMPRESSOR Filed Aug. 23, 1935 2 Sheets-Sheet l A W AT ORNEY'.

Oct. 23, 1934. $M|TH 1,977,740

MULTICYLINDER OSCILLATING PUMP OR COMPRESSOR Filed Afig. 23, 1953 2 Sheets-Sheet 2 i? 5. Wyn.

JNVENTOR, $22272 M ORNEY.

Patented Oct. 23, 1934 MULTICYLINDER OSCILLATING PUMP OR 7 COMPRESSOR FrankA. Smith, Seattle, Wash, assignor to Smith Manufacturing Company, a corporation of Washington Application August 23, 1933, Serial No. 686,400

6 Claims.

The invention consists in certain advanoements in this art as set forth in the ensuing dis-- closure and having, with the above, additional objects and advantages as hereinafter developed, and whose construction, combination and details of means, and the manner of operation will be made manifest in the description of the herewith illustrative embodiment; it being understood that modifications, variations and adaptations may be resorted to within the scope, principle and spirit of the invention as it is more directly claimed hereinafter.

Figure l is an axial section of the compressor housing, and

Figures 2 and 3 are inside face views of parts of the casing thereof, showing the respective flow ports.

Figure 4 is a sectional view of a multicylinder vacuum pump, and

Figures 5 and 6 are inside face views of parts of the casing thereof, showing the respective flow ports.

The compressor adaptation in Figure 1 includes a casing formed of two butt-faced sections 23 secured by bolts 4 and forming a chamber "4 1 5 in whose lower part is disposed a main shaft 6 provided with eccentric 7-8 in diametrically opposed assembly. The eccentric '7 has a radial piston 9 reciprocating in a cylinder 10 mounted for oscillation on a hollow trunnion 11 through 457 which extends a cooling core 12, and the eccentric 8 has a piston 13 in a cylinder 14 oscillating on trunnion 11.

This trunnion is fixed in the head of the casing 2, whose inner side faces have lands 1516 against which the respective cylinders are firmly thrust for lateral bearing by an intermediate spring 17.

The cylinder 10 has a lateral port 10 which as the piston 9 starts down registers for a moment with intake port 10 in the land face 15 and as the piston 10 completes its compression or up stroke the port 19 registers with outlet port 10 in the land face 15.

In a similar manner a port 14 of cylinder 14 alternately registers with intake port 14 and outlet port 14) in land 16.

For the purpose of compounding the pressure in the machine the pistons 9 and 13 are of different'diameters, the latter being the smaller.

' The outlet l0 leads to a cooling coil 20 which delivers the compressed gas by line 21 to the intake port 14 of the cylinder 14, to be greatly increased in density by the high pressure piston 13, for ultimate discharge.

The port 10 is preferably valved at 15 in 70. Fig. 1. i In the modification shown in Figure 4, the casing 25 journals a shaft 26 having diametrically opposite eccentrics 27-28 with radial pistons 29-30 working in respective cylinders 31-32 oscillating on a trunnion 33 in the head of the. casing.

These cylinders have abutting side faces 3 1 with mutual ports 31* ---32 which intermittently meet on the compression stroke of the piston 29 80. and intake stroke of piston 30.

The cylinder 31, has an inlet port 31 in a lateral face bearing on land wall 2 of the casing and c linder 32 has an outlet port 32 passing to a Valve cup 34' of the cylinder and slidably fite5 ting in a discharge duct 35. In this duct is a spring 36 bearing against the cup 34 and acting to thrust the cylinder faces 34 firmly together and pressing the cylinder 31 firmly against the wall 2 The suction port 31", being in connection with any chamber to be evacuated, will induct to the cylinder 31 when the piston 29 nears bottom down stroke. On up stroke piston 29 compresses the charge and then ports 31 --32 meet and the Q5 compressed charge passes to cylinder 32 which has been evacuated by down stroke of its piston 36. Relative swing of the cylinders 3132 causes ports Sl -32 to close and aspiston 30 comes to top the port 32 opens to outlet 34', thus in- 109 creasing the evacuating effort of the machine.

What is claimed is:

1. In multi-stage apparatus of the class described, the combination of a shaft, a plurality of eccentrics, pistons which are arranged I05 apart on the shaft, cylinders for the respective pistons, a bearing on which the cylinders coaxially oscillate, said cylinders having lateral ports, a casing having side walls with ports for cooperation with respective cylinder ports, means for 2 the passage of the discharge from one cylinder to the other, and resilient means for maintaining a sealing pressure of all surfaces, of the cylinders, contiguous to coordinate ports in the said parts.

2. Inmulti-stage apparatus of the class described, the combination of a shaft, a plurality of eccentrics, pistons which are arranged 180 apart on the shaft, cylinders for the respective pistons, a bearing on which the cylinders axially oscillate, said cylinders having lateral ports, a casing having side walls'withports for cooperation with respective cylinder ports, means for the passage of the discharge from one cylinder to the other, and resilient means for maintaining a sealing pressure of all surfaces, of the cylinders, contiguous to coordinate ports in the said parts, and for pressing the cylinders one against the other.

3. In multi-stage apparatus of the class described, the combination of a shaft, a plurality of eccentrics, pistons which are arranged 180 apart on the shaft, cylinders for the respective pis tons, a bearing on which the cylinders coaxially oscillate, said cylinders having lateral ports, a casing having side walls with ports for cooperation with respective cylinder ports, means for the passage of the discharge from one cylinder to the other, and resilient means for maintaining a sealing pressure of all surfaces, of the cylinders, contiguous to coordinate ports in the said parts, and for pressing the cylinders one against the other; said passagemeans being located in the butting faces of the last mentioned cylinders for direct flow from one to the other.

.' pistons, a bearing on which the cylinders'coaxially oscillate, said cylinders having lateral ports, a casing having side walls with ports for cooperationwith respective cylinder ports, means for .a casinghaving side walls with ports for cooperapistons, a bearing on which the cylinders coaxially oscillate, said cylinders having lateral ports, 9

0 tion with respective cylinder ports, means for the passage of the discharge from one cylinder to the other, andresilient means for maintaining a sealing pressure of all surfaces, of the cylinders, contiguous to coordinate ports in the said parts; said passage means including a discharge passage from one cylinder to a cooler and a conduit between said cooler to the intake of the other cylinder and said spring means being interposed and reacting between the cylinders. 6. In multi-stage apparatus of the class described, the combination of a shaft, a plurality of eccentrics, pistons which are arranged 180 apart on the shaft, cylinders for the respective pistons, a bearing on which the cylinders coaxially oscillate, said cylinders having lateral ports, a casing having side walls with ports for cooperation with respective cylinder ports, means for the passage of the discharge from one cylinder to the other, and resilient means for maintaining a sealing pressure of all surfaces, of the cylinders, contiguous to coordinate ports in the said parts, one of the side walls provided with a cup valve in which the wall port is formed and said resilient means acting against said cup and thereby applying its efforts to press the cylinders together and against the opposite wall. v

' J FRANK A. SMITH. 

